The present invention concerns a method for colour printing and magnetic encoding of plastic cards, in particular pre-paid cards, smart cards and the like.
The invention comprises also a compact, reliable, efficient, low-cost machine embodying said method.
There is a huge and fast development and commercial use in every field of the so called smart-cards.
Consequently there has been a parallel development of processes, systems and machines for the plastic cards identification, implementing the different technologies that have been brought about in the last 20 years.
The field of said methods, systems, machines and the like is now-a-day a so-called patent crowded field.
Among the most important aspects of this recent and continuously improving technology we have to emphasize the following:                1) Magnetic Encoding, 2) Thermal Printing, 3) Printing Ribbon Colour Detection, 4) Control of the Heat Energy feed to the Thermal Printing.        
About aspect 1), there is a large number of patents, such as WO/0016235 and U.S. Pat. No. 5,941,522 that mostly concern the mechanical complexity of the design of a Plastic Card Printer including a Magnetic Encoder. Generally, however, the encoding is carried out after (downstream along the card path) the Printing, whereby there is the drawback that cards that are printed well may nevertheless be poorly downloaded because they have undergone a bad encoding with a non-negligible card waste.
As to item 2) we limit ourselves to cite U.S. Pat. No. 5,486,057.
European Patent Application Publication n. 0 299 653 A2 concerns a Method and Apparatus for the Thermal Printing and the relevant Thermal Heat feeding.
Several systems and methods for the Ribbon Colour Detection have been proposed and implemented, such as those described in WO 00/34050, EP Publications N. 0189574 A2 and N. 0 624 480 A2 and French Pat. Pub. N. 2 783 460 A1.
UK Patent Application N. 2 258 550 A, International Patent Publication WO 96/06739 and EP Publication 0 573 336 A1, concern the Thermal Printing Control through the control of the Heat feed to the Printing Head.
Moreover, up to now, the overall printing, encoding, colour detecting, and printing thermal control have been managed by an electronic system based on a CPU (Central Processing Unit), that implements for each control aspect a SW (Software) driver which has to execute its function at the same time, all together and in real time.
The computational complexity of all these drivers, executed in multitasking, has required the use of CPUs with increasing performances and resources, which generally are expensive and difficult to manage.
Accordingly, the methods and apparatus described in the Published Patent Literature show, together with several merits, also many decisive and conditioning inconveniences. Just to mention a major drawback, the conventional apparatus must have a longitudinal length of at least four times the major dimension of a card.
First object of the present invention is to provide a general method which eliminates the drawbacks and insufficiencies of the Prior Art, in particular of the Art according to the above mentioned Patents.
Another object of the present invention is to provide a compact, reliable, efficient and low cost machine implementing said method.